1. Field of the Invention
The present invention relates to a transfer apparatus designed to transfer workpieces at different pitches by means of a plurality of transfer bars.
2. Discussion of the Prior Art
In transfer machines, generally, a plurality of working stations are disposed in series along the production line in such a manner that the stations are spaced apart from each other, and workpieces are successively transferred from one working station to another by means of a transfer apparatus. There has heretofore been one type of transfer apparatus known as two-pitch transfer apparatus in which each pair of working stations are provided in close proximity with each other and workpieces are transferred from one working station to the other at two different transfer pitches for the purpose of reducing the floor area required for installation of the transfer machine.
If the arrangement is such that a plurality of transfer bars are moved at different pitches by means of a known mechanical transfer apparatus that utilizes a driving motor as a drive source, the overall size of the transfer apparatus is considerably increased, resulting disadvantageously in an increase in the floor area occupied by the apparatus.
The above-described problem experienced with the conventional mechanical transfer apparatus in attributable to its arrangement. More specifically, in this prior art, a gear box having a driving motor installed therein and a guide means which slidably supports a slider block having a transfer bar connected thereto are installed separately and independently of each other. The gear box supports a driving arm which is pivoted by means of the driving motor through a reduction gear mechanism, and a roller is rotatably supported at the distal end of the driving arm. The roller is engaged with a vertical groove formed in the slider block, so that the slider block is reciprocated at a predetermined stroke in response to the pivotal motion of the driving arm.